hive计算示例
先将数据通过sqoop从mysql导入hive，在hive执行mysql的查询语句，得到与mysql一样的执行结果
步骤：- mysql数据准备
- account账号表
- detail收支数据表
CREATE TABLE `account` (
`id` int(11) PRIMARY KEY AUTO_INCREMENT,
`account` varchar(20),
`name` varchar(5),
`age` int(3)
);
insert into account(account, name, age) values("tom@qq.com", "Tom", 23);
insert into account(account, name, age) values("jack@qq.com", "Jack", 20);
insert into account(account, name, age) values("jone@qq.com", "Jone", 22);
insert into account(account, name, age) values("jimi@qq.com", "Jimi", 25);
insert into account(account, name, age) values("black@qq.com", "Black", 24);
select * from account;
CREATE TABLE `detail` (
`id` int(11) PRIMARY KEY AUTO_INCREMENT,
`account` varchar(20),
`income` double,
`expenses` double,
`time` varchar(10)
);
insert into detail(account, income, expenses, time) values("tom@qq.com", 10, 20, 2018-12-1);
insert into detail(account, income, expenses, time) values("jack@qq.com", 10, 30, 2018-12-4);
insert into detail(account, income, expenses, time) values("jone@qq.com", 13, 22, 2018-12-3);
insert into detail(account, income, expenses, time) values("jimi@qq.com", 45, 25, 2018-12-2);
insert into detail(account, income, expenses, time) values("black@qq.com", 34, 24, 2018-12-1);
insert into detail(account, income, expenses, time) values("tom@qq.com", 50, 20, 2018-12-1);
select * from detail;
- 创建hive表
create table account (
id int,
account string,
name string,
age int
) row format delimited fields terminated by '\t';
create table detail (
id int,
account string,
income double,
expenses double,
time string
) row format delimited fields terminated by '\t';
- 通过sqoop将mysq当中的数据直接导入到hive当中
sqoop import
--connect jdbc:mysql://localhost:3306/mydata
--username root
--password 123456
--table account
--hive-import
--hive-overwrite
--hive-table account
--fields-terminated-by '\t'
sqoop import --connect jdbc:mysql://localhost:3306/mydata --username root --password 123456 --table detail --hive-import --hive-overwrite --hive-table detail --fields-terminated-by '\t'
- 计算结果，mysql和hive中计算结果一致
select a.account, a.name, d.total
from account as a
join(
select account, sum(income - expenses) as total
from detail group by account
) as d
on a.account=d.account;
mysql计算结果
+--------------+-------+-------+
| account | name | total |
+--------------+-------+-------+
| black@qq.com | Black | 10 |
| jack@qq.com | Jack | -20 |
| jimi@qq.com | Jimi | 20 |
| jone@qq.com | Jone | -9 |
| tom@qq.com | Tom | 20 |
+--------------+-------+-------+
hive计算结果
black@qq.com Black 10.0
jack@qq.com Jack -20.0
jimi@qq.com Jimi 20.0
jone@qq.com Jone -9.0
tom@qq.com Tom 20.0
报错：
/tmp/hive on HDFS should be writable.
解决
> hadoop fs -chmod -R 777 /tmp
报错：
Could not load org.apache.hadoop.hive.conf.HiveConf. Make sure HIVE_CONF_DIR
解决：
往/etc/profile最后加入
export HADOOP_CLASSPATH=$HADOOP_CLASSPATH:$HIVE_HOME/lib/*
然后刷新配置，source /etc/profile
